· Technology
 · · Networking

Network Too Slow? · I’m em­bed­ded at the Mother­ship here in Sil­ly Val­ley all week, and among oth­er things, heard about a prod­uct I nev­er dreamed ex­ist­ed. Check it out: the IB Switch 9p; it’s a nine-port In­fini­band switch, non-blocking even, each port up to 30Gbs and no, that’s not a mis­print. Why nine, I won­der? My poor lit­tle mind bog­gles at the thought of what you could do with a rack full of ei­ther Opterons or T2000s, maxed out on mem­o­ry and wired up with one of these things. To­day, store.­sun.­com says one of these pup­pies will set you back $8,500; I imag­ine that in a decade, there’ll be one in your wrist­watch to han­dle your per­son­al teleme­try.
Latency · [For Java/net­work­ing geeks on­ly.] I have these two Ja­va pro­gram­s, talk­ing through an or­di­nary TCP/IP sock­et. The client sends a (medium-sized) se­ri­al­ized ob­ject to the server, which does a lit­tle bit of com­pu­ta­tion and ac­knowl­edges by send­ing a (s­mal­l) ob­ject back. Straight writeOb­jec­t()/read­Ob­jec­t() calls with setTcpNoDe­lay(true) in ef­fec­t. When both of them are run­ning on my 1.25Ghz Pow­erBook here, the la­ten­cy re­quired for the whole trans­ac­tion is like 190m­sec, which is hor­ri­ble. So I moved the serv­er code down to the mouldy old P300 De­bian box in the base­men­t, talk­ing to it over two or three legs of WiFi and Eth­er­net switch­es, and the la­ten­cy dropped to around 33m­sec; still not great, but the dif­fer­ence is in­struc­tive.
author · Dad · software · colophon · rights
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